Primary signet ring cell carcinoma of the prostate.

A 61-year-old Korean man was referred to our institution because of high prostate-specific antigen (PSA) (8.1ng/mL) and frequency, nocturia that had lasted for the previous 4 months. The first transrectal ultrasonography (TRUS)-guided prostate biopsy result was benign prostatic hyperplasia. About 3 years later, the patients revisited our institute for elevated PSA (14.7 ng/mL) and back pain. The patient underwent a second TRUS-guided prostate biopsy. Histological examination and immunohistochemical staining showed a signet ring cell carcinoma (SRCC). Also there were multiple bony metastasis. Androgen deprivation therapy (ADT) was started. Nine months later, the patient was diagnosed with hormone refractory prostate cancer and the ADT was changed into docetaxel chemotherapy. The patient died after 2 cycles of chemotherapy. We report this case of a SRCC of the prostate and review the literature.